• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.669-675
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• 2008

Carbon black has been widely used in composites, tonor resin, and ink materials. Since carbon black readily agglomerates, it is important to disperse carbon black in real applications. Aiming to improve dispersion stability, carbon black was chemically oxidized to possess hydroxyl groups using a phase transfer catalyst at room temperature. The modified carbon black (CB-OH) was grafted by a silane coupling agent, p-methylacryloxypropyltrimethoxysilane, to carry teminal vinyl groups. The modified carbon black was subsequently used in miniemulsion polymerization to achieve encapsulted core-shell structure. Finally, well-encapsulated carbon black by polymer was obtained in the size range of 100-500 nm. Throughout the polymerization, the effects of surface modification, types of monomers, initiators, and emulsifiers were investigated.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1593-1595
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• 1999

Effects of carbon black species and concentration on the mechanical and electrical properties of alumina trihydrate filled EPDM compounds were investigated. Mechanical properties improved with increasing carbon black concentration, and these effects were prominent in carbon blacks haying large specific area. In the case of non-conductive carbon black. tracking resistance improved when a small amount of carbon black was added to EPDM. Conductive carbon black showed detrimental effect to dielectric losses, volume resistivity and tracking resistance of EPDM compound.

• Asian Journal of Atmospheric Environment
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• v.10 no.1
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• pp.1-12
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• 2016

Numerous researchers have proposed that surface area is a more appropriate indicator than mass for evaluating pulmonary inflammatory responses caused by exposure to fine and ultrafine particles. In this study, measurements of surface area concentrations of aerosols were conducted in Yokohama, Japan, using the diffusion charging method. $PM_{2.5}$ mass concentration and black carbon concentration in $PM_{2.5}$ were also measured. The 24-hour continuous measurement campaigns were conducted 39 times from March to November, 2014. The surface area concentration was more closely correlated with the black carbon concentration than with the $PM_{2.5}$ mass concentration. It is considered that the abundance of black carbon particles significantly affects the surface area concentration of $PM_{2.5}$. The strength of the correlation between the surface area and black carbon concentrations varied considerably among the measurement campaigns. A relatively weaker afternoon correlation was observed compared with the other time zones (morning, evening, and night). We consider that these phenomena are due to the transportation/formation of the particles other than black carbon that affects surface area concentration and/or the variation of the surface condition of the black carbon particles.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.136-137
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• 2005

To measure elastic properties of semiconducting materials in power cable, we have investigated modulus of EBA/carbon black composite showed by changing the content of carbon black. The specimen was primarily kneaded in material samples of pellet form for 5 minutes on rollers ranging between 70[$^{\circ}C$] and 100[$^{\circ}C$]. Then this was produced as sheets after pressing for 20 minutes at 180[$^{\circ}C$] with a pressure of 200[kg/cm]. The contents of conductive carbon black were 20, 30 and 40[wt%], respectively. The modulus experiment was measured by DMA 2980. The ranges of measurement temperature were from -50[$^{\circ}C$] to 100[$^{\circ}C$] and measurement frequency is 1 [Hz]. The modulus of specimens was increased according to an increment of carbon black content And modulus was rapidly decreased at the glass transition temperature. The tan$\delta$ of specimens was decreased according to an increment of carbon black content.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.363-369
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• 2008

In the present work, the choice of the nano carbon black and optimum mixed ratio and effectiveness of the mixed carbon black to get a raw data for a manufacturing method of conductive complex board. Optimum mixed ratio of paper sludge & water was 1 : 2.5 for reformations. HB-41-Y was cheaper than Super-P with the single carbon black. Also electric conductivity of HB-41-Y($6.406{\times}10^{-2}\;{\Omega}cm^{-1}$) was about 6.5 times higher than Super-P($9.741{\times}10^{-3}\;{\Omega}cm^{-1}$) at 20 wt% carbon black. This time optimum mixture ratio of the paper sludge and the carbon black to be about 15 wt%, optimum mixed ratio HB-41Y and Graphite about 3:1 and its electric conductivity was $5.824{\times}10^{-2}\;{\Omega}cm^{-1}$.

• Elastomers and Composites
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• v.7 no.1
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• pp.21-37
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• 1972

We have studied the blending effects of Diene NF 35R and Turfdene 1000R at various blending ratios 100/0, 70/30, 50/50, 30/70, 0/100, and of carbon black NAF and ISAF at various compounding ratios of 55 PHR, 65PHR, 75PHR for tyre tread rubber. As the results, it was found that; 1. For tyre tread rubber, as the blending ratio, Diene NF 35R/Turfdene 1000R, indicated 30/70, the physical properties we examined were most excellent. 2. Excellent result was obtained in case of carbon black compounding ratio of 63PHR. The compounding of ISAF made better result than that of HAF for tensile strength, tearing strength, and abrasion quantity. 3. Heat buildup obtained from compounding carbon black HAF indicated low temperature than that from compounding carbon black ISAF. As the compounding amount of carbon black increased, the heat buildup improved, and as the blending amount of Diene NF 35R decreased, the heat buildup dropped. 4. Carbon black was more efficient to Turfdene 1000R than to Diene NF 35R. 5. In this pysical properties, mooney viscosity, and mooney scorch time, as the compounding amount of carbon black increased, the values of mooney viscosity increased, but that of mooney scorch time dropped.

• Carbon letters
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• v.8 no.2
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• pp.115-119
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• 2007

Properties of carbon blacks and carbon black/SBR rubber composites filled by surface modified carbon blacks were examined. Although the specific surface area of carbon blacks increased after the surface modifications with heat, acid, and base, there were no obvious changes in resistivity. The composites filled by heat treated carbon blacks showed a higher tensile strength and elongation than those filled by raw blacks. The acid and base treated carbon blacks filled composites also showed higher tensile strength but similar elongation values with those filled by raw blacks. With increasing loading ratio, both tensile strength and elongation increased, and appeared a maximum value at 30-40 phr. Modulus at 300% strain remained increasing with further loading of carbon blacks. At the same loading, the heat treated black filled composites showed similar modulus values with composites filled by raw blacks but for base and acid treated black filled composites much higher values were obtained. After the surface modification, the functional groups which played an important role in reinforcement action were changed.

• Toxicological Research
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• v.29 no.2
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• pp.121-127
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• 2013

Nanotoxicological research has shown toxicity of nanomaterials to be inversely related to particle size. However, the contribution of agglomeration to the toxicity of nanomaterials has not been sufficiently studied, although it is known that agglomeration is associated with increased nanomaterial size. In this study, we prepared aerosols of nano-sized carbon black by 2 different ways to verify the effects of agglomeration on the toxicity and deposition of nano-sized carbon black. The 2 methods of preparation included the carbon black dispersion method that facilitated clustering without sonication and the carbon black dispersion method involving sonication to achieve scattering and deagglomeration. Male Sprague-Dawley rats were exposed to carbon black aerosols 6 hr a day for 3 days or for 2 weeks. The median mass aerodynamic diameter of carbon black aerosols averaged $2.08{\mu}m$ (for aerosol prepared without sonication; group N) and $1.79{\mu}m$ (for aerosol prepared without sonication; group S). The average concentration of carbon black during the exposure period for group N and group S was $13.08{\pm}3.18mg/m^3$ and $13.67{\pm}3.54mg/m^3$, respectively, in the 3-day experiment. The average concentration during the 2-week experiment was $9.83{\pm}3.42mg/m^3$ and $9.08{\pm}4.49mg/m^3$ for group N and group S, respectively. The amount of carbon black deposition in the lungs was significantly higher in group S than in group N in both 3-day and 2-week experiments. The number of total cells, macrophages and polymorphonuclear leukocytes in the bronchoalveolar lavage (BAL) fluid, and the number of total white blood cells and neutrophils in the blood in the 2-week experiment were significantly higher in group S than in normal control. However, differences were not found in the inflammatory cytokine levels (IL-$1{\beta}$, TNF-${\alpha}$, IL-6, etc.) and protein indicators of cell damage (albumin and lactate dehydrogenase) in the BAL fluid of both group N and group S as compared to the normal control. In conclusion, carbon black aerosol generated by sonication possesses smaller nanoparticles that are deposited to a greater extent in the lungs than is aerosol formulated without sonication. Additionally, rats were narrowly more affected when exposed to carbon black aerosol generated by sonication as compared to that produced without sonication.

• Journal of Conservation Science
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• v.20
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• pp.55-65
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• 2007

Black surface layers collected from stone pagodas were analyzed to study the effects of carbon compounds on the blackening of stone surface layer. The total amounts of carbon was measured through elemental analyser. Organic and elemental carbon were measured by combustion ihrornatographic $CO_2$ determination after elimination of carbonates carbon with acid treatment. The elemental carbon concentration in the black surface layer measured 0.52wt.%. This value is not sufficient to explain the complete blackening of stone surface. To trace the origin of carbon in black surface layer on the stone pagoda, aerosol samples for PM 10 were collected at the near sites of the pagoda. The major components of them were soluble ions(42.8wt.%), carbon(38.4 wt.%) and crustal matter(16wt.%). From the high content(13wt.%) of elemental carbon in aerosol ran be deduced that it may be a prime origin for the elemental carbon in the black surface layer on the stone pagoda. The crustal matter in aerosol can be also a origin of silicate mineral in black surface layer and plays a important role in the darkening of black surface layer.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.223-226
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• 2005

For $CO_2-free$ hydrogen production and better utilization of the produced carbon, catalytic decomposition of methane over rubber-grade carbon blacks manufactured from coal tar was carried out. The catalytic activities of several domestic carbon blacks were compared. A pelletized carbon black exhibited considerably lower activity and activation energy than the fluffy( loose) carbon black of the same grade. This difference is considered due to the binder that was added during pelletization. For pelletized carbon blacks, a tendency was observed that the activity per unit mass of catalyst increased with the specific surface area of the carbon black. Another tendency was also observed that the activation energy increased with the primary particle size or decrease of the specific surface area.